Docking system including first and second optical transceivers for docking and related methods

ABSTRACT

A docking system may include a first device and a second device moveable relative to the first device. The first device may include a docking station, a first optical transceiver, and a first controller configured to operate the first optical transceiver to receive an optical beacon signal, and generate and transmit an optical guidance data signal based on the optical beacon signal. The second device may also include a propulsion system, and a second optical transceiver configured to transmit the optical beacon signal toward the first optical transceiver and receive the optical guidance data signal from the first optical transceiver. The second device may also include a second controller configured to operate the propulsion system based upon the optical guidance data signal to dock the second device to the docking station of the first device.

TECHNICAL FIELD

The present invention relates to the field of networks, and moreparticularly, to underwater communications networks and related methods.

BACKGROUND

A communications network is a group of nodes interconnected by linksthat are used to exchange messages between the nodes. The links may usea variety of technologies based on the methodologies of circuitswitching, message switching, or packet switching, to pass messages andsignals.

One type of network is a seafloor network. A seafloor network istypically used by industry, government and academia to observe andrecord measurements in the environment and transmit data over longdistances. Traditional deployments of seafloor networks may berelatively expensive and typically involve manual connections on thesurface and lowering the cable and equipment to the seafloor.

Relatively large cable ships are typically used along with acorresponding crew for cable installation operations. Both the ships andcrew may be exposed to relatively harsh environmental conditions duringdeployments and installation operations.

PCT Application Publication No. WO 2016/200386 discloses aself-deploying and self-healing subsea network that includes one or morehoming vehicles, one or more data repeaters, and one or more independentguidable homing systems configured to assist the homing vehicles inlocalization of and docking with the data repeaters. Data repeaters aredeployed in a body of water and, at a predetermined time, a homingvehicle is released from a first data repeater and instructed to transitto and dock with a predetermined second data repeater. After docking, anetwork cable is operatively placed into communication between the firstdata repeater and the second data repeater.

U.S. Pat. No. 8,831,393 to Jung is directed to an unmanned underwatervehicle and device for connection of an optical waveguide cable to anunmanned underwater vehicle. More particularly, Jung discloses unmannedunderwater vehicles that can be controlled from a carrier platform by anoptical waveguide cable. The optical waveguide cable is to be connectedto the underwater vehicle via a connecting device. The connecting deviceincludes a connecting cable and connecting elements at the ends of theconnecting cable for an optical waveguide cable at one end and for anunmanned underwater vehicle at the other end.

SUMMARY

A docking system may include a first device and a second device moveablerelative to the first device. The first device may include a dockingstation, a first optical transceiver, and a first controller configuredto operate the first optical transceiver to receive an optical beaconsignal, and generate and transmit an optical guidance data signal basedon the optical beacon signal. The second device may include a propulsionsystem, and a second optical transceiver configured to transmit theoptical beacon signal toward the first optical transceiver and receivethe optical guidance data signal from the first optical transceiver. Thesecond device may also include a second controller configured to operatethe propulsion system based upon the optical guidance data signal todock the second device to the docking station of the first device.

The first controller may be configured to determine at least one of arange, a bearing, a velocity, a roll, and a pitch of the second deviceand generate the optical guidance data signal based thereon, forexample. The second device may include a long-range navigation devicecoupled to the second controller.

The second controller may be configured to operate the propulsion systembased upon the long-range navigation device. The long-range navigationdevice may include an inertial navigation system (INS), for example.

At least one of the first and second devices may include an opticalcable storage device. The first and second optical transceivers mayinclude first and second laser transceivers. The first and second lasertransceivers may include first and second vertical cavity surfaceemitting laser transceivers, for example.

The second device may include an underwater vehicle. The second devicemay include a space vehicle. The second device may include a terrestrialvehicle, for example. The second device may include an airborne vehicle.

A method aspect is directed to a method of docking a second devicemoveable relative to a first device. The method may include using afirst controller of the first device to operate a first opticaltransceiver of the first device to receive an optical beacon signal, andgenerate and transmit an optical guidance data signal based on theoptical beacon signal. The method may also include using a secondcontroller of the second device to cooperate with a second opticaltransceiver of the second device to transmit the optical beacon signaltoward the first optical transceiver and receive the optical guidancedata signal from the first optical transceiver, and operate a propulsionsystem of the second device based upon the optical guidance data signalto dock the second device to a docking station of the first device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of an underwater communications network inaccordance with an embodiment.

FIG. 2 is a schematic diagram of a node of FIG. 1.

FIG. 3 is a more detailed schematic diagram of a UUV of a node of FIG.1.

FIG. 4A is a schematic diagram of an exemplary node configuration of anunderwater communications network in accordance with an embodiment.

FIG. 4B is a schematic diagram of an exemplary node configuration of anunderwater communications network in accordance with an embodiment.

FIG. 4C is a schematic diagram of an exemplary node configuration of anunderwater communications network in accordance with an embodiment.

FIG. 5 is a schematic diagram of an exemplary node in accordance with anembodiment.

FIG. 6 is another schematic diagram of the exemplary node of FIG. 5.

FIG. 7 is a schematic diagram of a docking system in accordance with anembodiment.

FIG. 8 is a schematic block diagram of the docking system of FIG. 7.

FIG. 9 is a schematic diagram of an exemplary implementation of adocking system in accordance with an embodiment.

DETAILED DESCRIPTION

The present invention will now be described more fully hereinafter withreference to the accompanying drawings, in which preferred embodimentsof the invention are shown. This invention may, however, be embodied inmany different forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art. Likenumbers refer to like elements throughout, and prime notation is used toindicate similar elements in alternative embodiments.

Referring initially to FIGS. 1-3, an underwater communications network20 includes spaced apart nodes 30 a-30 n on a bottom 22 of body of water21, for example, a seafloor. While three nodes 30 a-30 n areillustrated, those skilled in the art will appreciate that there may beany number of nodes. The nodes may be deployed from the air, the surfaceor subsea, with manned or unmanned platforms, for example.

The underwater communications network 20 also includes fiber opticcabling 40 that connects the spaced apart nodes 30 a-30 n. The fiberoptic cabling 40 may include one or more sensing optical fibers 41 a-41n. For example, the fiber optic cabling 40 may include a sensor 44 ordefine a sensor so that it has sensing properties such that vibration,temperature, and pressure may be sensed. Moreover, a squeezing of theoptical cabling 40 may change the properties of the cabling, which maybe used to identify hazards or used as a basis for changing the topologyof the underwater communications network 20 (e.g., by way of nodelocations).

Each node 30 a-30 n includes a frame 31 a-31 n and an unmannedunderwater vehicle (UUV) 32 a-32 n carried by the frame after deliveringa fiber optic cable 40 (e.g., which may be used for sensing) of thefiber optic cabling 40 along a navigation path from an adjacent node.The frame 31 a-31 n may include one or more docking stations 35 a-35 nfor receiving the UUV 32 a-32 n therein. For example, the dockingstation 35 a-35 n may be in the form of a garage defined by the frame 31a-31 n. The docking station 35 a-35 n may be in another form or locationrelative to the frame 31 a-31 n, for example, alongside the frame. EachUUV 32 a-32 n may be self-deployed or autonomous between adjacent nodes30 a-30 n, for example, based upon coordinates of the nodes.

Each node 30 a-30 n also includes a node short-range navigation device38 a-38 n carried by the frame 31 a-31 n. The node short-rangenavigation device 38 a-38 n may be any one or more of a short-rangeacoustic navigation device (e.g., acoustic pinger), short-range opticalnavigation device (e.g., optical reflector), and a short-rangeradio-frequency (RF) navigation beacon, for example. Of course the nodeshort-range navigation device 38 a-38 n may include other and/oradditional types of short-range navigation devices using differentnavigation techniques. Each UUV 32 a-32 n cooperates with thecorresponding node short-range navigation device 38 a-38 n during an endportion of the navigation path adjacent the frame 31 a-31 n, forexample, using a UUV short range navigation device 45 a-45 n. In otherwords, cooperation of the UUV and the node short-range navigationdevices 38 a-38n, 45 a-45 n guides each UUV 32 a-32 n into the dockingstation 35 a-35 n when it is in range.

Each node 30 a-30 n, and more particularly, each UUV 32 a-32 n may alsoinclude a node long-range navigation device 39 a. The node long-rangenavigation device 39 a is for the UUV and operates as the UUV travelsalong the navigation path, for example, from the adjacent node. Thoseskilled in the art will appreciate that the node long-range navigationdevice 39 a may guide the UUV 32 a-32 n along the navigation path, forexample, using global positioning or other longer range navigationtechniques, and up to an in-range position with the node short-rangenavigation device 38 a-38 n. In an embodiment, the node long-rangenavigation device 39 a may be used in conjunction with the nodeshort-range navigation device 38 a-38 n during the end portion of thenavigation path.

Each node 30 a-30 n may also include communications circuitry 33 a-33 ncoupled to the fiber optic cabling 40, and more particularly, torespective ones of the fiber optic cables 40. The fiber optic cable 40permits communication between adjacent nodes 30 a-30 n, and may performsensing operations, as described above.

The communications circuitry 33 a-33 n of each node 30 a-30 n is poweredby a power source 34 a-34 n. The power source 34 a-34 n may be apre-equipped on-board power source, such as, for example, a battery, anexternal add-on source through an auxiliary connector, an inside (e.g.,via a docking station 35 a-35 n) hardwired connection, and/or an inside(e.g., via the docking station) wireless connection for example. Ofcourse, the power source 34 a-34 n may be another type of power source.

The power source 34 a-34 n may also power either or both of the nodeshort-range and long-range navigation devices 38 a-38 n, 39 a.

At least one node 30 a from among the spaced apart nodes 30 a-30 nincludes a deployable electronic buoy 60 that is carried by the frame 31a. The deployable electronic buoy 60 may be a deployable electronicsensor buoy, for example, and include one or more of a vibration sensor,a temperature sensor, and a pressure sensor. The deployable electronicbuoy 60 may also be a deployable electronic wireless communicationsbuoy, and include one or more wireless receivers and/or transmitters.More than one node 30 a-30 n may include a deployable electronic buoy60.

In some embodiments, the node or nodes 30 a-30 n including thedeployable electronic buoy 60 may include a winch 70 carried by theframe 31 a-31 n for controllably deploying the deployable electronicbuoy to the surface 23 of the body of water 21. By being at the top orsurface 23 of the body of water 21, the deployable electronic buoy 60may wirelessly communicate based upon line-of-sight or withcommunications satellites, which may be prohibitive on the bottom 22 ofthe body of water or seafloor. The deployable electronic buoy 60, whencommunicating above the surface 23 of the body of water 21, may acquireinstructions and/or position information that may be used for deploymentof the underwater communications network 20 or UUVs 32 a-32 n, forexample.

As will be appreciated by those skilled in the art, the spaced apartnodes 30 a-30 n may be considered lander nodes, and the fiber opticcabling 40 may be small, ultra-strong, highly-integrated (SUSHI) fiberoptic cable links that are carried by the UUVs 32 a-32 n. The UUVs 32a-32 n may be self-deploying or autonomous, for example. The links andnodes can be arranged to form various network configurations. Referringbriefly to FIGS. 4A-4C, three exemplary network configurations of nodes,denoted by circles, and links, denoted by arrowed lines, areillustrated—point-to-point (FIG. 4A), redundant (FIG. 4B), and mesh(FIG. 4C)—the nodes of which may correspond to the spaced apart nodes 30a-30 n and the links of which may correspond to the delivered fiberoptic cables 40.

A single UUV 32 a-32 n is typically used to assemble each link, whichmay be performed by traversing from its home lander or node 30 a to anadjacent destination node 30 b or lander and paying out the fiber opticcable 40 along its path. Fiber optic cable terminations may be hardwiredat the source or home node 30 a. When the UUV 32 a-32 n docks in itsdestination node, an optical network connection is made wirelessly orthrough a magnetic connection, as will be described in further detailbelow. A relatively simple network configuration includes a single UUV32 a-32 n and a single (empty) docking station 35 a-35 n, which can forma point-to-point configuration as illustrated in FIG. 4A. Each node 30a-30 n may be modularly expanded to include more than one UUV 32 a-32 nand associated docking stations 35 a-35 n as desired, for example, toestablish redundant paths and point-to-multi-point (P2MP) connections asillustrated in FIGS. 4B and 4C. The quantity of network ports, and hencesize of the node 30 a-30 n, is thus scalable.

Further technical details of exemplary nodes 30 a-30 n will now bedescribed. With respect to each node 30 a-30 n, and more particularly,the frame 31 a-31 n of each node, the node may be conceptually similarto those used on the Triton 36000/2 Hadal Exploration System availablefrom Triton Submarines, LLC of Sebastian, Fla.

The winch 70 of each node 30 a-30 n may be a subsea winch, for example,a MER1VIAC™ electrically driven winch available from MacMartneyUnderwater Technology of Denmark. The winch 70 advantageously controlsthe deployment of communications equipment and sensors by raising andlowering the deployable electronic buoy 60, for example, at pre-definedor commanded intervals, speeds, and depths by way of a cable 71. Thewinch 70 may operate in relatively harsh underwater environments. Toaccommodate the relative harsh underwater environments, the motor andcontrol electronics, as well as the slip ring of the winch 70 may all beencapsulated, and may be manufactured from structural steel so toaccommodate a depth of 500 m and 3,200 m cable capacities. In someembodiments, the winch 70 may include steel-armored and PUR jacketcables.

As described above, each winch 70 controls a respective deployableelectronic buoy 60, which may be embodied as a communications and/orsensor float (FIG. 2). When the deployable electronic buoy 60 is in theform of a deployable electronic wireless communications buoy,communications can be above and below the surface 23 of the body ofwater 21, for example, by using a hybrid software defined radio (modem)with optical, acoustic and/or RF transceiver capability. When thedeployable electronic buoy 60 is in the form of a deployable electronicsensor buoy, one or more sensors may collect information from theenvironment above and below the surface 23 of the body of water 21. Anexemplary sensor may include a relatively small hydrophone, which canalert to unexpected activity on the surface 23 or unsafe sea conditions.In some embodiments, the deployable electronic buoy 60 may rise to thesurface 23 of the body of water 21 when no activity or threat of damageis detected. Once at the surface 23 of the body of water 21, thedeployable electronic buoy 60 may communicate based upon line of sight(LOS), beyond line of sight (BLOS) and satellite communications(SATCOM), for example, by using several different waveforms based uponthe type of application (e.g. high-bandwidth exfiltration, command andcontrol infiltration, LPI/LPD text messages, etc.).

Referring now briefly to FIGS. 5-6, an exemplary node 30 a′illustratively includes four docking stations 35 a′-35 d′ forcorresponding UUVs 32 a′ 32 b′. The docking stations 35 a′-35 d′ permitthe UUVs 32 a 32 b′ to enter in one direction, into a larger“fly-catcher” side. Many techniques have been used to guide a UUV into adocking station. For example, the IVER4 UUV available from L3HarrisCorporation of Melbourne, Fla. has been used to successfully dock insideof 21-inch tubes or docking stations. In some embodiments, a node 30 a′may include at least one empty docking station 35 c′, 35 d′ and at leastone docking station 35 a′, 35 b′ that is equipped with a UUV. An emptydocking station 35 c′, 35 d′ may provide a power and optical data pathinto the node 30 a′ to tie the associated link into the larger network,for example, by way of the communication circuitry 33 a′-33 n′,described above.

Foam, for example, syntactic foam 36′ may be placed in a top portion ofeach node 30 a′, and relatively heavy items and desired drop weights 37′may be placed at a bottom of each node. This may advantageously permitthe nodes 30 a′ to be “dropped” from the surface or another elevationabove the seafloor. The nodes 30 a′ remain upright during free fallwithout any fins or other devices to keep them vertical.

Referring again to FIGS. 1-3, with respect to network connections, thefiber optic cabling 40 or fiber optic network connections are terminatedinside each node 30 a-30 n. Optical links may couple the UUVs 32 a-32 nto the fixed connections via wireless protocol, for example, or amagnetic coupling arrangement as described in U.S. Pat. No. 9,816,856,assigned to the present assignee, and the entire contents of which arehereby incorporated by reference. Relatively small form factor protocols(SFPs) convert the fiber optic data to electrical signals inside thenetwork media converters and connect to the network traffic via therouter switches.

With respect to power sources 34 a-34 n, each power source, may usealuminum-water (Al—H2O) technology. This technology may provide arelatively safe, cost competitive, and energy dense approach for staticand dynamic components. The Al—H2O technology uses aluminum as a fuel togenerate electricity and produces an inert byproduct. Power modules orsources may be customized to meet desired specifications. Additionalports on the nodes 30 a-30 n accommodate external battery packs, forexample.

With respect to sensors, sensors may be integrated into the nodes 30a-30 n and/or the deployable electronic buoy 60, as described above.Sensors may include passive hydrophones or distributed fiber opticsensors to detect acoustic and seismic signatures generated by underseaand surface vehicles or environmental effects. Of course, other and/oradditional sensors may be used. The sensors may cooperate with thecommunications circuitry 33 a-33 n and/or other processing circuitrycarried by the frame 31 a-31 n of each node 30 a-30 n.

With respect to fiber optic cabling 40, the network links may includethe UUV 32 a-32 n, particularly a modified IVER UUV available fromL3Harris Corporation of Melbourne, Fla., and a SUSHI fiber optic cablepayload, also available from L3Harris Corporation. The use of a SUSHIfiber optic payload may offer innovative features, such as, for example,low-loss silica, a standard acrylate buffer, an added buffer, arelatively high packing density, relatively high-tenacity aramid fibers,a robust jacket wall, and/or nanoparticle density modifiers. In summary,SUSHI can be customized for its desired usage based on the environment.For example, the diameter can be reduced to allow for longer linklengths; strength members can be added to increase the break strength tobetter withstand abrasions encountered on the seafloor; and the buoyancycan be controlled to reduce drag on the UUV during deployment.

It may be desirable to have a free-flooded payload section of the UUV 32a-32 n equipped with precision wound cable packs. This may lend itselfto a relatively easy deployment and payout. Nodes 30 a-30 n may bescaled to achieve desired cable length links.

Accordingly, the underwater communications network 20 may beparticularly advantageous for its ability to be scalable andconfigurable in multiple pre-defined and software re-configurabletopologies. For example, the underwater communications network 20 may beparticularly useful for establishing a communications network betweenoil rigs, and does not involve dropping of cable from the back of boats.Additionally, the underwater communications network 20 connectsautonomously using self-deployed and self-docking UUVs 32 a-32 n topayout and terminate node-to-node cable links on the seafloor. Moreover,as will be appreciated by those skilled in the art, to decommission theunderwater communications network 20 or any node or nodes 30 a-30 ntherein, their respective links may be disconnected (physically and/orelectronically) between the UUV 32 a-32 n and the respective nodes(autonomously or commanded). If decommissioning is desired, the UUVs 32a-32 n and the nodes 30 a-30 n may be disposed by electronic scuttle andcathodic corrosion.

A method aspect is directed to a method of forming an underwatercommunications network 20. The method includes deploying a plurality ofspaced apart nodes 30 a-30 n on a bottom 22 of a body of water 21. Themethod includes connecting the plurality of spaced apart nodes 30 a-30 nwith fiber optic cabling 40. Each node 30 a-30 n includes a frame 31a-31 n, and an unmanned underwater vehicle (UUV) 32 a-32 n carried bythe frame after delivering a fiber optic cable 40 thereto, and at leastone node 31 a of the plurality of spaced apart nodes including adeployable electronic buoy 60 carried by the frame.

While several embodiments have been described herein, it should beappreciated by those skilled in the art that any element or elementsfrom one or more embodiments may be used with any other element orelements from any other embodiment or embodiments. In other words,different embodiments or variations of nodes and UUVs may be used withinthe underwater communications network 20. For example, a node with asingle docking station (FIGS. 1 and 2) may be used with a node with fourdocking stations (FIGS. 5-6).

Referring now to FIGS. 7 and 8, in another embodiment, a docking system120, for example, may be usable with the underwater communicationsnetwork 20 described above. The docking system 120 illustrativelyincludes a first device 132 a and a second device 132 b. The seconddevice 132 b is movable relative to the first device 132 a. The firstdevice 132 a may be in the form of or include an optical cable storagedevice, for example.

The second device 132 b may be in the form of an underwater vehicle, forexample, an unmanned underwater vehicle. The second device 132 b mayalternatively be in the form of a space vehicle. The second device 132 bmay be in the form of a terrestrial vehicle. The second device 132 b mayalso be in the form of an airborne vehicle. The second device 132 b maybe in the form of or include an optical cable storage device.

The first device 132 a includes a docking station 135 a, for example,for receipt of the second device 132 b therein or thereat, depending onthe form of the second device. The first device 132 a also includes afirst optical transceiver 138 a. The first optical transceiver 138 a maybe a first laser transceiver for example, a first vertical cavitysurface emitting laser (VCSEL). The first optical transceiver 138 a mayoperate in the blue or blue-green color spectrum. In some embodiments,for example, terrestrial and/or aerial, the first optical transceiver138 a may operate in a range of wavelengths, for example, just outsideof the visible spectrum (e.g., 900-2000 nm). This may increase thedifficulty in detection, which may be desirable in certain operations orapplications, as will be understood by those skilled in the art.

The first device 132 a may also include a first controller 150 a thatoperates the first optical transceiver 138 a to receive an opticalbeacon signal 152 and generate and transmit an optical guidance datasignal 153 based on the optical beacon signal. The optical guidance datasignal 153 may be for directing, controlling, or for steering the seconddevice 132 b, as will be described in further detail below. The firstcontroller 150 a may determine a one or more of a range, a bearing, avelocity, a roll, and a pitch of the second device 132 b. The firstcontroller 150 a may thus generate the optical guidance data signal 153based upon any one of the range, the bearing, the velocity, the roll,and the pitch of the second device 132 b, as will be appreciated bythose skilled in the art.

The second device 132 b illustratively includes a propulsion system 155b. The propulsion system 155 b may include different hardware orconfigurations depending on the application or type of device or vehiclethat is the second device 132 b. For example, when the second device 132b is in the form of an underwater vehicle, the propulsion system 155 bmay include a propeller or impeller, rudder, and power plant (e.g.,driveshaft, and battery or engine). When the second device 132 b is inthe form of a space vehicle, the propulsion system 155 b may includerockets, rocket boosters, and/or other spaced-based propulsioncomponents, as will be appreciated by those skilled in the art. When thesecond device 132 b is in the form of a terrestrial vehicle, thepropulsion system 155 b may include an engine or battery, driveshaft,and wheels or tracks, for example. For an airborne vehicle, thepropulsion system 155 b may include an engine or batteries, adriveshaft, and one or more propellers or turbofans (vertically orhorizontally oriented), for example. Of course, other components orcombination of components may be used to define the propulsion system155 b.

The second device 132 b also includes a second optical transceiver 138b. Similarly to the first optical transceiver 138 a, the second opticaltransceiver 138 b may be a second laser transceiver for example, asecond vertical cavity surface emitting laser (VCSEL). The secondoptical transceiver 138 b may operate in the blue or blue-green colorspectrum. In some embodiments, for example, terrestrial and/or aerial,the second optical transceiver 138 b may operate in a range ofwavelengths, for example, just outside of the visible spectrum (e.g.,900-2000 nm).

The second optical transceiver 138 b transmits the optical beacon signal152 toward the first optical transceiver 138 a. The second opticaltransceiver 138 b also receives the optical guidance data signal 153from the first optical transceiver 138 a.

The second device 132 b also includes a second controller 150 b thatoperates the propulsion system 155 b to dock the second device to thedocking station 135 a of the first device 132 a. More particularly, thesecond controller 150 b selectively operates the propulsion system 155 bbased upon the optical guidance data signal 153 so that the seconddevice is guided to or into the docking station 135 a.

In some embodiments, the second device 132 b may include a long-rangenavigation device 139 b, for example, along the lines of the long-rangenavigation device described above. The long-range navigation device 139b is coupled to the second controller 150 b, which operates thepropulsion system 155 b based upon the long-range navigation device. Inother words, the long-range navigation device 139 b operates thepropulsion system 155 b to move the second device 132 b along anavigational route until it becomes in range of communication betweenthe first and second optical transceivers 138 a, 138 b. Once in range,the second controller 150 b operates the propulsion system 155 b to dockthe second device 132 b at the docking station 135 a. Of course, thelong-range navigation device 139 b may work in conjunction with thefirst and second optical transceivers 138 a, 138 b to dock the seconddevice 132 b at the docking station 135 a.

Those skilled in the art will appreciate that the long-range navigationsystem 139 b may include global positioning system (GPS) receivers, RFreceivers, accelerometers, and/or devices, for example, and include aninertial navigation system (INS).

As will be appreciated by those skilled in the art, the first and secondoptical transceivers 138 a, 138 b are advantageously used for bothimaging and communications. That is, the first and second opticaltransceivers 138 a, 138 b communicate therebetween optical beaconsignals 152 (imaging) and optical guidance data signals 153(communications).

The docking system 120 that includes the second device 132 b in the formof an airborne vehicle, may be advantageous for assisting a dronelanding on a platform at sea (ship, buoy, etc.), refueling aircraft withanother aircraft (drone applications), unmanned aerial vehicle(UAV)-to-UAV avoidance or wireless tethering for specialized formationflying, for example. The docking system 120 that includes the seconddevice 132 b in the form of a terrestrial vehicle, may assist in robot,refueling ships at sea with another vessel (e.g., drone applications),and in automotive industry for self-docking or self-parking vehicles,for example.

When the docking system 120 includes the second device 132 b in the formof a space vehicle, the docking system may assist in the docking ofspacecraft (vehicle) docking into a space station, spacecraft (vehicle)servicing a satellite, a lander releasing vehicle drones to investigateplanetary surface (e.g., Mars rovers) and the drones navigating back tothe lander. The docking system 120 that includes a space vehicle mayalso be advantageous for satellite-to-satellite avoidance or wirelesstethering for specialized formation flying, for example.

Those skilled in the art will appreciate that when the docking system120 includes the second device 132 b in the form of an underwatervehicle, the docking system may be particularly advantageous for dockinginto spaced apart nodes, as described above, docking into a dockingstation or bay on another vehicle (e.g., UUV onto a submarine, or ROVonto a submarine bay). The second vehicle 132 b in the form of anunderwater vehicle may also be advantageous in offshore oil and gasoperations, for example, for servicing oil and gas infrastructure. Thesecond vehicle 132 b in the form of an underwater vehicle may also beadvantageous for USV-to-USV or AUV-to-AUV tethering for strategicformation, and/or USV-to-AUV situational awareness navigating inrelatively tight areas around structures, for example.

Referring now additionally to FIG. 9, further details of the dockingsystem 120′ as it relates an undersea application will now be described.The docking system 120′ uses the first and second optical transceivers138 a′, 138 b′ as an optical modem pair. It may desirable, however, toincludes additional photon collectors adjacent the docking station, forexample, three, for homing and docking functionality to remotely guidethe second device 132 b′ in the form of an incoming undersea vehicleinto a docking station of the first device 132 a′. The docking system120′ does not rely on an imaging lens to determine range and bearing ofthe incoming vehicle (i.e., second device). Instead the rising edge orphase shift of an expanding optical wavefront generated with a lightemitting diode (LED) or photo acoustic tomography (PAT)-capablelaser-based optical communications modem (i.e., the second opticaltransceiver 138 b′) is detected. Such a self-radiating optical beacon152′ may operate over at least 16 one-way diffuse beam attenuationlengths (up to 300 meters in the clear coastal ocean) versus 2-3 one-waydiffuse attenuation lengths with a camera method, and 5-6 one-wayattenuation lengths with a LiDAR.

The docking system 120′ processing is based upon multi-lateration, whichis also referred to as hyperbolic positioning. This technique usesmultiple spatially separated transmitters or receivers to estimate theposition of one receiver or transmitter (i.e., GPS). This is done bycalculating the time difference of arrival (TDOA) from the time ofarrival (TOA) of each transmitter to the receiver or from thetransmitter to each receiver and computing the position using thehyperbolic method described by Bucher et al., as will be appreciated bythose skilled in the art.

For a 3D positioning system, at least four receivers may be desirable toreduce ambiguities and improve accuracy. The most common methods tomeasure TOA are direct time of flight (TOF) measurements and extractionof relative TOA from the phase of a continuous sinusoidal signal. Tomeasure TOF directly, a short pulse may be used, and the difference inarrival times is used to determine TOA. When a continuous sinusoidalwaveform is used for the transmitter, the relative TOA can be extractedfrom the detected phase difference of two synchronized signals (i.e. tworeceivers observing the same signal).

In similar applications, an array detector (i.e., a camera) andstructured illumination (i.e., a laser line or grid of laser dots) maybe used to estimate both the range and azimuthal/elevation angles to themoving target. However, due to multiple scattering effects that occurover multiple scattering lengths in typical coastal conditions, cameraor flash-LiDAR based systems generally do not provide effectiveperformance over the wide range of conditions typically encountered. Theuse of pulsed or modulated laser source waveforms, combined with a smallarray of single element detectors with non-imaging optics (i.e. bucketcollectors that are used for optical modems)—such as described hereinwith respect to the docking system 120′, may provide useful data througha wider range of conditions and also simplifies the calibration process,measurement setup, and reduces the amount of data to be collectedcompared to the use of multiple structured lighting cameras orflash-LiDAR imagers and their associated high speed image/videoprocessing algorithms. In some embodiments, the docking system 120′ mayuse orbital angular momentum beams to better discriminate direct(ballistic) light through the many scattering lengths, as will beappreciated by those skilled in the art.

As described above, and with respect to an embodiment where the seconddevice 132 b′ is in the form of a UUV, the UUV transmits, via the secondoptical transceiver 138 b′, the optical beacon signal 152′ in adirection of a known docking station on a first device 132 a′. Eachreceiver element of an array thereof of the first optical transceiver138 a′ detects the optical beacon signal 152′, which is directional. Thefirst transceiver 138 a′ or first optical modem, as described above,illustratively includes three additional receivers 158 a′ that areconfigured or positioned to define a triangle.

The second controller based upon a TDOA, computes the range and bearing(both elevation and azimuthal bearing). The first optical transceiver138 a′ transmits to the UUV, or second device 132 b′, the relativedisplacement and suggested waypoints.

A method aspect is directed to a method of docking a second device 132 bmoveable relative to a first device 132 a. The method includes using afirst controller 150 a of the first device 132 a to operate a firstoptical transceiver 138 a of the first device to receive an opticalbeacon signal 152, and generate and transmit an optical guidance datasignal 153 based on the optical beacon signal. The method also includesusing a second controller 150 b of the second device 132 b to cooperatewith a second optical transceiver 138 b of the second device to transmitthe optical beacon signal 152 toward the first optical transceiver 138 aand receive the optical guidance data signal 153 from the first opticaltransceiver, and operate a propulsion system 155 b of the second devicebased upon the optical guidance data signal to dock the second device toa docking station 135 a of the first device 132 a.

Many modifications and other embodiments of the invention will come tothe mind of one skilled in the art having the benefit of the teachingspresented in the foregoing descriptions and the associated drawings.Therefore, it is understood that the invention is not to be limited tothe specific embodiments disclosed, and that modifications andembodiments are intended to be included within the scope of the appendedclaims.

That which is claimed is:
 1. A docking system comprising: a first deviceand a second device moveable relative to said first device, said firstdevice comprising a docking station, a first optical transceiver, and afirst controller configured to operate said first optical transceiver toreceive an optical beacon signal, and generate and transmit an opticalguidance data signal based on the optical beacon signal; said seconddevice comprising a propulsion system, a second optical transceiverconfigured to transmit the optical beacon signal toward the firstoptical transceiver and receive the optical guidance data signal fromsaid first optical transceiver, and a second controller configured tooperate said propulsion system based upon the optical guidance datasignal to dock said second device to said docking station of said firstdevice.
 2. The docking system of claim 1 wherein said first controlleris configured to determine at least one of a range, a bearing, avelocity, a roll, and a pitch of said second device and generate theoptical guidance data signal based thereon.
 3. The docking system ofclaim 1 wherein said second device comprises a long-range navigationdevice coupled to said second controller; and wherein said secondcontroller is configured to operate the propulsion system based upon thelong-range navigation device.
 4. The docking system of claim 3 whereinsaid long-range navigation device comprises an inertial navigationsystem (INS).
 5. The docking system of claim 1 wherein at least one ofsaid first and second devices comprises an optical cable storage device.6. The docking system of claim 1 wherein said first and second opticaltransceivers comprise first and second laser transceivers.
 7. Thedocking system of claim 6 wherein said first and second lasertransceivers comprise first and second vertical cavity surface emittinglaser transceivers.
 8. The docking system of claim 1 wherein said seconddevice comprises an underwater vehicle.
 9. The docking system of claim 1wherein said second device comprises a space vehicle.
 10. The dockingsystem of claim 1 wherein said second device comprises a terrestrialvehicle.
 11. The docking system of claim 1 wherein said second devicecomprises an airborne vehicle.
 12. A first device for a docking systemincluding a second device being moveable relative to a first device, thefirst device comprising: a docking station; a first optical transceiver;and a first controller configured to operate said first opticaltransceiver to receive an optical beacon signal from a second opticaltransceiver of the second device, generate and transmit an opticalguidance data signal based on the optical beacon signal so that thesecond optical transceiver receives the optical guidance data signalfrom said first optical transceiver and cooperates with a secondcontroller of the second device to operate a propulsion system of thesecond device based upon the optical guidance data signal to dock thesecond device to said docking station.
 13. The first device of claim 12wherein said first controller is configured to determine at least one ofa range, a bearing, a velocity, a roll, and a pitch of said seconddevice and generate the optical guidance data signal based thereon. 14.The first device of claim 12 wherein at least one of said first andsecond devices comprises an optical cable storage device.
 15. The firstdevice of claim 12 wherein said first and second optical transceiverscomprise first and second laser transceivers.
 16. The first device ofclaim 15 wherein said first and second laser transceivers comprise firstand second vertical cavity surface emitting laser transceivers.
 17. Asecond device for a docking system, the second device moveable relativeto a first device, the second device comprising: a propulsion system; asecond optical transceiver configured to transmit an optical beaconsignal toward a first optical transceiver of the first device andreceive an optical guidance data signal based upon the optical beaconsignal from the first optical transceiver; and a second controllerconfigured to operate said propulsion system based upon the opticalguidance data signal to dock the second device to a docking station ofthe first device.
 18. The second device of claim 17 wherein said seconddevice comprises a long-range navigation device coupled to said secondcontroller; and wherein said second controller is configured to operatethe propulsion system based upon the long-range navigation device. 19.The second device of claim 18 wherein said long-range navigation devicecomprises an inertial navigation system (INS).
 20. The second device ofclaim 17 wherein said first and second optical transceivers comprisefirst and second laser transceivers.
 21. The second device of claim 17wherein said second device comprises one of an underwater vehicle, aspace vehicle, a terrestrial vehicle, and an airborne vehicle.
 22. Amethod of docking a second device moveable relative to a first device,the method comprising: using a first controller of the first device tooperate a first optical transceiver of the first device to receive anoptical beacon signal, and generate and transmit an optical guidancedata signal based on the optical beacon signal; and using a secondcontroller of the second device to cooperate with a second opticaltransceiver of the second device to transmit the optical beacon signaltoward the first optical transceiver and receive the optical guidancedata signal from the first optical transceiver, and operate a propulsionsystem of the second device based upon the optical guidance data signalto dock the second device to a docking station of the first device. 23.The method of claim 22 wherein using the first controller comprisesusing the first controller to determine at least one of a range, abearing, a velocity, a roll, and a pitch of the second device andgenerate the optical guidance data signal based thereon.
 24. The methodof claim 22 wherein the using the second controller comprises using thesecond controller to operate the propulsion system based upon along-range navigation device coupled to the second controller.